Wai Khru Ram Muay (Thai: ไหว้ครูรำมวย, rtgs: wai khru ram muai, IPA:[wâːj kʰrūː rām mūɛj]) is a warm up activity in Thai culture that is performed by participants in Muay Thai competitions. Wai is an action of Thais to show respect to others by putting the hands together like in prayer. Khru means teacher. Ram means dance in the old Thai traditional style. Muay means boxing. Usually Thais prefer to call it Ram Muay or Wai Khru for short. Ram Muay is the way to show respect to the teachers and the trainers. Also, in the past Muay Thai was usually fought in front of the King, so Ram Muay was also to apologize to the King for the brutality in fighting.

The fighter then performs the Ram Muay, whose simple movements demonstrate a fighter's control and style. Each fighter performs the Ram Muay on each side of the ring to demonstrate his prowess to the audience. The Ram Muay is a personal ritual, ranging from the very complex to the very simple, and often contains clues about who trained the fighter and where the fighter is from.

The practitioner may wear a headband called a Mongkhon and armbands known as Pra Jiad during the ceremony, and the Ram Muay may be accompanied by music. The Mongkhon is unique to Thai boxing and not worn in Cambodia or Burma.